perf cs-etm: Remove unused stub methods

These aren't used outside of cs-etm so don't need stubs. Leave
cs_etm__process_auxtrace_info() which is used externally, and add an
error message so that it's obvious to users why it causes errors.

Signed-off-by: James Clark <james.clark@arm.com>
Cc: Al Grant <Al.Grant@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Garry <john.g.garry@oracle.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suzuki Poulouse <suzuki.poulose@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: coresight@lists.linaro.org
Cc: linux-arm-kernel@lists.infradead.org
Link: https://lore.kernel.org/r/20221212155513.2259623-3-james.clark@arm.com


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>